Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, a generator, a gearbox, a nacelle, and one or more rotor blades. The rotor blades capture kinetic energy of wind using known foil principles. The rotor blades transmit the kinetic energy in the form of rotational energy so as to turn a shaft coupling the rotor blades to a gearbox, or if a gearbox is not used, directly to the generator. The generator then converts the mechanical energy to electrical energy that may be deployed to a utility grid.
Typically, the rotor blades are mounted on a hub and aerodynamically interact with the wind. In order to improve efficiency for capturing the wind energy, it is usually needed to adjust blade pitch to a desired blade pitch angle after the blade is assembled to the hub. Currently, the alignment between the blade and hub is carried out by manually marking the blade and hub in factory and manually aligning the marks in the field where the wind turbine is mounted. However, the manual alignment may introduce high variance and high probability of errors. Misalignment may cause annual energy output (AEP) lost. For example, 3-degree deviation may cause 5% AEP loss. Moreover, misalignment may cause high turbine vibration, and cause un-symmetrical force and worsen working load to the turbine, which may generate damage and significantly reduce the service life of wind turbine components.
Accordingly, a new blade alignment method and a wind turbine which can align its blades with the method are desirable.